Silver ammonia complex chloride

Qualitative. The classic method for the quaUtative determination of silver ia solution is precipitation as silver chloride with dilute nitric acid and chloride ion. The silver chloride can be differentiated from lead or mercurous chlorides, which also may precipitate, by the fact that lead chloride is soluble ia hot water but not ia ammonium hydroxide, whereas mercurous chloride turns black ia ammonium hydroxide. Silver chloride dissolves ia ammonium hydroxide because of the formation of soluble silver—ammonia complexes. A number of selective spot tests (24) iaclude reactions with /)-dimethy1amino-henz1idenerhodanine, ceric ammonium nitrate, or bromopyrogaHol red [16574-43-9]. Silver is detected by x-ray fluorescence and arc-emission spectrometry. Two sensitive arc-emission lines for silver occur at 328.1 and 338.3 nm. 

In a linear complex, the coordination number is 2, corresponding to one group on each side of the central atom. The silver-ammonia complex, which generally forms when a very slightly soluble silver salt such as silver chloride dissolves in aqueous ammonia, is an example, as shown in Figure 22-6. Another example of a linear com-... 

The silver chloride (AgCl) is dissolved as the stable silver-ammonia-complex ion [Ag(NH3) 2+] is formed. Meanwhile, the mercury II chloride (HgCl2) is undergoing oxidation and reduction at the same time Mercury metal (Hg) and mercury II amidochloride (HgNH2Cl) are formed and appear, respectively, black and gray in color ... 

The mercury substances are filtered, and silver ions (Ag+) are detected in the filtrate by adding hydrochloric acid (HC1), which releases the silver ions from the silver-ammonia-complex ion [Ag(NH3) 2+], allowing the silver ions to combine with chloride ions (Cl") to form silver chloride precipitate (AgCl) ... 

The silver ammonia complex, Ag(NH8)2, is sufficiently stable for ammonium hydroxide to dissolve precipitated silver chloride by re-ducing the concentration of silver ion, [Ag+], below the value required for precipitation by the solubility product of AgCl. A satisfactory test for silver ion is the formation with chloride ion of a precipitate which is soluble in ammonium hydroxide. 

Ores of silver native silver, argentite, cerargyrite (horn silver). Metallurgy of silver cyanide process, amalgamation process, Parkes process. O mpoimds of silver silver oxide, silver chloride, silver bromide, silver iodide, silver ammonia complex, silver cyanide complex, silver thiosulfate complex, silver nitrate. 

Dilute the remaining silver ammonia complex test solution with water and flush it down the drain with water. Destroy all solid silver acetylide salt by treatment with hydrochloric acid. Collect the silver chloride and put it in a container for heavy metals, and then flush the filtrate down the drain. 

Silver chloride will dissolve in aqneons ammonia because of the formation of a complex ion. Lead chloride will not dissolve it doesn t form an ammonia complex. 

Softer Lewis bases have to be applied in etch baths for oxides and salts of metals or semiconductors with a softer Lewis acid character of their cations. Materials consisting of compounds of heavier metals frequently become dissolvable in the presence of higher halogenide imis like chloride or bromide. So, Cu(l) which is not well solvated in water as the unbound ion becomes dissoluble in the presence of, for example, chloride ions by forming Cu(l) chlorocomplexes. The choice of suitable complex ligands depends on the particular coordination chemistry of the heavier metals or semiconductors inside the oxidic or saltlike functional materials. In some cases, ammonia or amines are suitable. So, the formatiOTi of a silver diamine complex can be used for the etching of Ag(l) compounds,... 

The complexes of copper(I) like those of silver(I) (p. 430), but unlike those of preceding transitions metals, tend to prefer a linear coordination of two ligands, i.e. X—Cu—X thus copper(I) chloride in aqueous ammonia gives the colourless [Cu(NH3)2] (readily oxidised in air to give blue [Cu (NH3)4(H20)2] copper(I) chloride in hydrochloric acid gives [CuClj], although [CuCl3] is also known. 

Silver chloride is readily soluble in ammonia, the bromide less readily and the iodide only slightly, forming the complex cation [Ag(NH3)2]. These halides also dissolve in potassium cyanide, forming the linear complex anion [AglCN) ] and in sodium thiosulphate forming another complex anion, [Ag(S203)2] ... 

Ammonia forms a great variety of addition or coordination compounds (qv), also called ammoniates, ia analogy with hydrates. Thus CaCl2 bNH and CuSO TNH are comparable to CaCl2 6H20 and CuSO 4H20, respectively, and, when regarded as coordination compounds, are called ammines and written as complexes, eg, [Cu(NH2)4]S04. The solubiHty ia water of such compounds is often quite different from the solubiHty of the parent salts. For example, silver chloride, AgQ., is almost iasoluble ia water, whereas [Ag(NH2)2]Cl is readily soluble. Thus silver chloride dissolves ia aqueous ammonia. Similar reactions take place with other water iasoluble silver and copper salts. Many ammines can be obtained ia a crystalline form, particularly those of cobalt, chromium, and platinum. 

Silver Bromide. Silver bromide, AgBr, is formed by the addition of bromide ions to an aqueous solution of silver nitrate. The light yellow to green-yeUow precipitate is less soluble in ammonia than silver chloride, but it easily dissolves in the presence of other complexing agents, such as thiosulfate ions. 

Silver Chloride. Silver chloride, AgCl, is a white precipitate that forms when chloride ion is added to a silver nitrate solution. The order of solubility of the three silver halides is Cl" > Br" > I. Because of the formation of complexes, silver chloride is soluble in solutions containing excess chloride and in solutions of cyanide, thiosulfate, and ammonia. Silver chloride is insoluble in nitric and dilute sulfuric acid. Treatment with concentrated sulfuric acid gives silver sulfate. 

Consider now a somewhat different type of complex ion formation, viz. the production of a complex ion with constituents other than the common ion present in the solution. This is exemplified by the solubility of silver chloride in ammonia solution. The reaction is ... 

At this point, the silver and mercury(I) chlorides remain as precipitates. When aqueous ammonia is added to the solid mixture, the silver precipitate dissolves as the soluble complex ion Ag(NH3)2+ forms ... 

At this point, any Hg22+ has precipitated and any Ag+ present is in solution. The solution is separated from the solid, and the presence of silver ion in the solution is verified by addition of nitric acid. This acid pulls the ammonia out of the complex as NH4+, allowing white silver chloride to precipitate ... 

Remove the bath with water, remove the rubber tube with a bent glass tip from the end of the apparatus, and pass the carbon(II) oxide through ammonia solutions of silver nitrate and copper(I) chloride poured into test tubes. What happens Does the carbon(II) oxide exhibit the same properties in these reactions How can one prove that carbon(II) oxide will evolve when the formed complex compound of copper(I) is heated ... 

Anal. A freshly dried sample of product is added to water, aqueous ammonia is added, and the suspension is boiled for 15 min to destroy the complex and to reduce the Ag(II) to Ag(I) and the peroxydisulfate to sulfate. The resulting solution is acidified with dilute hydrochloric acid, and the silver is determined as silver chloride. Peroxydisulfate is determined by precipitation of the sulfate in the filtrate with barium chloride. Calcd. for Ag(C5H5N)4S208 Ag, 17.50 S2Oi-, 31.17. Found Ag, 17.90 S20 ", 31.32. 

The solubility of an ionic compound increases dramatically if the solution contains a Lewis base that can form a coordinate covalent bond (Section 7.5) to the metal cation. Silver chloride, for example, is insoluble in water and in acid, but it dissolves in an excess of aqueous ammonia, forming the complex ion Ag(NH3)2 + (Figure 16.13). A complex ion is an ion that contains a metal cation bonded to one or more small molecules or ions, such as NH3, CN-, or OH-. In accord with Le Chatelier s principle, ammonia shifts the solubility equilibrium to the right by tying up the Ag+ ion in the form of the complex ion ... 

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